Railroad crossing gates are in widespread use and are provided with long crossing arms for traffic barriers. The crossing arms are normally upright and are swung to a lowered, horizontal position when an approaching train is detected. The crossing arms of railroad crossing gates are provided with various signal lights that are secured to the crossing arm. Conventionally, three signal lights are used. A first light is disposed at the free end of the crossing arm. The remaining two lights are generally spaced along the crossing arm. It is conventional that the lights be incorporated into an electrical circuit such that the light at the free end is constantly illuminated when the crossing arm is in its horizontal position. The remaining signal lights are disposed in the electrical circuit such that they are flashing with the two lights alternately flashing off and on.
The environments in which railroad crossing gates are employed are numerous. For example, the crossing gates may be placed adjacent to railroad lines in urban areas where they span streets of widely varying widths. It can be difficult to timely identify malfunctioning crossing arms. There is a need in the art for a monitoring system that can alert an operator when the arm or lights thereon are malfunctioning.